Involuntary unemployment would necessarily be nil if the domestic economy did not include any dual production

This chapter demonstrates that, in the absence of production in the second sector, the Say’s law means the formal impossibility of any involuntary unemployment. As soon as the domestic economy includes the second sector, Say’s law remains perfectly valid but it is henceforth compatible with the existence of a positive unemployment. It is hard to imagine that the income created in the second sector should be lacking for the clearing of profit-goods. It is well known that this is so since the monetary profits made in the second sector are, by definition, absorbed in the wages issued to remunerate the producers of profit-goods. In order to ensure a return for the accumulated fixed capital, firms are left to find in the sale of wage-goods a profit in an increasing proportion of the income available in the economy.